Swift Dam (Montana)

Swift Dam is a dam in Pondera County, Montana, United States, on the southern end of the Blackfeet Indian Reservation.

The dam at was originally constructed around 1910, with a height of 157 ft. The embankment structure gave way on June 10, 1964, after heavy rains caused flooding on Birch Creek. The dam collapsed and sent a 30 ft wall of water down the creek bed. The nearby dam at Lower Two Medicine Lake also failed, and at least 28 people were killed.

The current concrete-arch structure was completed in 1967, with a height of 205 ft, and a length at its crest of 573 ft. The reservoir is also contained by a secondary earthen dike with a height of 53 ft and a length of 457 ft, also completed in 1967. The dams and reservoir are owned and operated by the local Pondera Canal & Reservoir Company.

The reservoir, Swift Reservoir, has a maximum storage capacity of 34000 acre feet, normal storage of 30000 acre feet, and a normal elevation of 1490 m. Recreation is restricted to hiking in the area, with a parking area that requires Blackfeet Nation permission.